What is the unit of electrical current?

Electrical quantities and units to memorize: CURRENT (I) = rate of charge flow = Amperes (A); VOLTAGE (V) = electrical potential difference, the 'push' that drives current = Volts (V); RESISTANCE (R) = opposition to current = Ohms (Ω); POWER (P) = rate of energy use = Watts (W); CHARGE (Q) = quantity of electricity = Coulombs (C); ENERGY = Joules (J) or kilowatt-hours (kWh) for electric utility. Mnemonic 'A Very Old Witch': Amp = A, Volt = V, Ohm = Ω, Watt = W. Plumbing analogy: voltage = water pressure, current = flow rate (gallons/second), resistance = pipe narrowness, power = total energy delivered. A garden hose with high pressure (V) and wide pipe (low R) delivers high flow (I). Definitions: 1 Ampere = 1 Coulomb of charge flowing past a point per second; 1 Volt = 1 Joule of energy per Coulomb of charge; 1 Ohm = the resistance allowing 1 Amp to flow under 1 Volt; 1 Watt = 1 Joule per second. Practical contexts: household outlets in US deliver 120V; appliances draw varying current (typical lamp ~0.5 A, hair dryer ~15 A, vacuum ~10 A); circuits have 15-20 A breakers; the wire size limits current capacity. AC vs DC: ALTERNATING CURRENT (AC) reverses direction periodically (60 Hz in US household wiring); DIRECT CURRENT (DC) flows one direction only (batteries, solar cells, USB power). Transformers work only with AC; electronics typically use DC internally (power supplies convert AC to DC).